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POComparing strings in C - strcmp
 

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  1. POComparing strings in C - strcmp
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    <p>I'm having trouble comparing strings in C (with which I am fairly new to). I have socket on this server application waiting to accept data from a client. In this particular portion of my program I want to be able to execute a MySQL query based on the data received from the client. I want to be able to know when the received data has the value of "newuser" to initiate a simple registration procedure. Strcmp is returning a positive 1 value where I believe I should be getting a 0 because the values should be equal.</p> <p>Source Code:</p> <pre><code>//setup socket //loop and select structure to handle multiple connections if ((nbytes = recv(i, buf, sizeof buf, 0)) &lt;= 0) { // got error or connection closed by client if (nbytes == 0) { // connection closed printf("selectserver: socket %d hung up\n", i); } else { perror("recv"); } close(i); // bye! FD_CLR(i, &amp;master); // remove from master set } else { char check[] = "newuser"; char fromUser[sizeof check]; strncpy(fromUser,buf, sizeof check); printf("length of fromUser: %d\n", sizeof fromUser); printf("length of check: %d\n", sizeof check); printf("message from user: %s\n", fromUser); printf("check = %s \n", check); int diff = strcmp(fromUser, check); printf("compare fromUser to check: %d\n", diff); if ( strcmp(fromUser, check) == 0) { printf("aha! new user"); } </code></pre> <p>Output:</p> <pre><code>length of fromUser: 8 length of check: 8 newuser from user: newuser check = newuser compare fromUser to check: </code></pre> <p>I have a feeling I'm not handling the incoming buffer correctly or erroneously copying the buffer.</p>
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    1. USEric de Araujo
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    1. COYou are not logging the fromUser value, only its length.
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